Screening for small molecules based on binding is of critical importance to many fields of modern medicine. Through the use of microarrays, it is possible to identify, for example, small molecules that are indicative of disease or illness. Currently, small molecule arrays (SMA), which is a maturing technology, are capable of hosting numerous reactants, proteins, and DNA samples.
High density microarrays are being used in a variety of medical and pharmaceutics practices to assist in identifying novel compounds or illness vectors. Currently, microarrays are being employed in fields such as clinical diagnostics, toxicology, genomics, drug discovery, environmental monitoring, genotyping and many other fields. A microarray is an orderly arrangement of samples containing a reactant. It provides a medium for matching known and unknown samples based on biochemical interactions and automating the process of identifying the unknowns. Microarrays available include oligonucleotide/DNA microarrays (see U.S. Pat. Nos. 6,291,170; 5,807,522 (inventors Shalon and Brown); U.S. Pat. Nos. 6,110,426; 5,716,785 and 5,891,636, (inventors Eberwine et al)). Reviewing the outcome of microarray experiments can entail viewing the arrays under UV (ultraviolet) light, as well as matching dispersion blots and patterns to know reference images. Machine and optical scanners have been developed to look at DNA chips and other expensive laboratory equipment. They include the cluster analysis of fluorescent images and other multiple pass image hybridization and compositing. (See U.S. Pat. No. 7,031,844; U.S. Patent Application Pub. 2004/0240718 and U.S. Patent Pub. 2005/0239114.)
Compound Arrays, or chemical “compound microarrays” (“CMA”), are microarrays that can provide chemical compounds with varying molecular weights immobilized on a medium. CMAs containing numerous unique chemical compounds attached to a biologically inert supporting surface provide for the identification of agents that modulate biological processes. For example, CMAs can be used to actively study the binding of proteins and enzymes or gene transcription. Proteins generally have binding sites for small molecules for important biological reasons. These molecules may act as substrates, inhibitors, activators, or even transcriptional regulators of the protein, interacting through one or more independent binding sites on the polypeptide.
CMAs are printed or deposited, as in a sequence of reservoirs for chemical compounds (a probe). These compounds are designed to react or bind with biological agents (reactant). For example, it is envisioned that CMAs could be probed so as to indicate the presence of specific protease genes and transcription enzymes that are indicative of a disease such as HIV. Thus, CMAs can be probed with an oligonucleotide probe and designed to emit phosphoresce when the reactants corresponding to reverse transcriptase and protease of polymorphic HIV-1 are found. Since these results are quickly obtainable, it is desirable to distribute more CMAs to geographical regions in need of additional medical testing apparatus.
The complexity of the hardware and analysis of the CMAs is a current barrier to the wide spread adoption of the technology in rural areas. Currently, on-site microarray analysis is difficult and expensive to undertake in areas lacking adequate and consistent access to electricity and other laboratory necessities. Furthermore, the nature of low medical service areas means that large and complex analysis apparatus are subject to extreme weather conditions and adverse treatment.